It’s clear that Intel looks at the Ultrabook concept it devised as a sort of kick in the pants for the PC industry. It thinks Windows-based, Intel-powered laptops should be thinner, lighter and cooler than they’ve usually been — and so it came up with Ultrabooks and is funneling money to the industry to make them.

Unlike some of its competitors, Sony doesn’t really need convincing. It’s been building slick, featherweight notebooks since long before the MacBook Air was so much as a gleam in Apple’s eye. So the company can be forgiven for being a bit late to the Ultrabook party: It’s just now announcing its first bona-fide Ultrabook, the VAIO T Series. It’s one of a bunch of new Sony PCs being announced today, including the latest version of what I think of as its ultra-Ultrabook, the VAIO Series Z. (Sony recently gave me a sneak peek at both.)

Sony

Intel has defined the Ultrabook spec loosely enough that PC manufacturers can go in a variety of directions, from building pricey, high-style systems to keeping things cheaper and simpler. The VAIO T13 is the latter sort of Ultrabook. It’s pretty darn straightforward, with an aluminum shell that packs a 13.3″ display with 1366-by-768 resolution, a choice of Intel’s Ivy Bridge ultra-low-voltage processors, a hybrid hard drive and a respectable complement of ports, including USB, VGA, HDMI, SD and Memory Stick. (It doesn’t, however, have a backlit keyboard.)

The T13 is .71″ thick and weighs 3.5 pounds, so it’s merely very travel-friendly rather than a competitor in the thinnest-and-lightest sweepstakes. It starts at $769.99 — on the low end for an Ultrabook.

If I were shopping for an Ultrabook and price were a major concern, the T would probably be on my list of contenders. But if I were looking for a super-portable computer and price was not an issue at all, the new Z Series — which isn’t technically an Ultrabook — would definitely be on it.

The Z has a 13.1″ screen with 1920-by-1080 (“Full HD”) resolution. Designwise, it bears some familial resemblance to the T, but it’s like the similarities between one of Toyota‘s less fancy models and a high-end Lexus. Its extra-handsome carbon-fiber case helps it achieve a weight of 2.6 pounds — almost a pound less than the T. It’s also thinner, at .66″.

Despite its lithe frame, the Z is available with quad-core processors and has two SSD bays, giving it a capacity of up to 512GB. It works with Sony’s optional Power Media Dock, which has a Blu-ray player and discrete AMD Radeon graphics, turning this reasonably powerful notebook into an even more powerful desktop. It’s also compatible with Sony’s sheet-battery technology, which lets you fasten a thin battery to its bottom, essentially turning it into a somewhat thicker, heavier laptop with longer battery life. (Sony quotes a figure of 14 hours and 30 minutes with the sheet battery — more than twice what it estimates without it.)

The Z Series starts at $1599.99 for a model with an Intel i5 processor, 8GB of RAM and 128GB of solid-state storage, plus extras such as a pair of noise-canceling earbuds. (You could buy two Series T Ultrabooks for that price.) But as long as I’m lusting after a dream machine, the one I’m craving is the top-of-the-line configuration. It’s got a quad-core i7 processor and 512GB of storage, and comes standard with the sheet battery — and costs $2999.99.

Both the T and Z, as well as other new VAIOs, will be available this month.